[Haskell-cafe] Typesafe multi-table PostgreSQL queries in Yesod with schema names?

[Erik de Castro Lopo]

Manuel Gómez wrote:

> Hi list,
> 
> I’m looking for a rather specific point in the design space for
> database access libraries in Haskell and I’m having some trouble
> figuring out whether any existing library covers my use cases.
> 
> Specifically, I need to
> 
> 1.  get a Yesod application to access a PostgreSQL database without
> having to reinvent the universe to get them decently integrated,
> 
> 2.  write queries in an EDSL with a good approach to composability and
> decent static verification against some declared form of the database
> objects,
> 
> 3.  be able to perform joins
> 
> 4.  be able to specify the schema name for each database object used in queries

<snip>

> *   Persistent: it’s perfectly integrated into Yesod, and together
> with Esqueleto, it provides a nice, typesafe and fully expressive EDSL
> — but, as far as I can tell, there is no support for specifying schema
> names, which is essential for my use case.


I'm not sure of what you mean here. DO you mean that you already have
a database and schema and you now want to connect Persisent/Esqueleto
to it without changing the existing schema?

Erik (a keen user of Persistent/Esqueleto)
-- 
----------------------------------------------------------------------
Erik de Castro Lopo
http://www.mega-nerd.com/